Urinary incontinence, or an inability to control urinary function, is a common problem afflicting people of all ages, genders, and races. Various muscles, nerves, organs and conduits within the urinary tract cooperate to collect, store and release urine. A variety of disorders may compromise urinary tract performance and contribute to incontinence. Many of the disorders may be associated with aging, injury or illness.
In some cases, urinary incontinence can be attributed to improper sphincter function, either in the internal urinary sphincter or external urinary sphincter. For example, aging can often result in weakened sphincter muscles, which causes incontinence. Some patients also may suffer from nerve disorders that prevent proper triggering and operation of the bladder or sphincter muscles. Nerves running though the pelvic floor stimulate contractility in the sphincter. A breakdown in communication between the nervous system and the urinary sphincter can result in urinary incontinence.
Electrical stimulation of nerves in the pelvic floor may provide an effective therapy for a variety of disorders, including urinary incontinence. For example, an implantable neurostimulator may be provided to deliver electrical stimulation to the sacral nerve to induce sphincter constriction and thereby close or maintain closure of the urethra at the bladder neck. An appropriate course of neurostimulation therapy may be aided by a sensor that monitors physiological conditions with the urinary tract. In some cases, an implantable stimulation device may deliver stimulation therapy based on the level or state of a sensed physiological condition.